Our long rang goal is to further understanding of the dynamic interrelationships of the gonads and the anterior pituitary. We are investigating the possible role of prolactin as the inhibitor of LH and FSH secretion after adrenalectomy by the use of biomoergocryptine. Similarly, we are using this inhibitor of prolactin to see if the prolactin secreted after pentobrabital treatment on diestrus is responsible for the blockade of LH release the next afternoon. We are testing the responsiveness of serum FSH to folliculostatin in genetic males which were feminized perinatally, and genetic females which were masculinized perinatally, to see if the sex differences in sensitivity of normal rats is altered. We are continuing our attempts to purify folliculostatin. finally, we will examine the effects of hypothalamic lesions on suppressibility of FSH (and LH) by steroids and folliculostatin.